diff --git a/packages/query-core/src/query.ts b/packages/query-core/src/query.ts
index 3c19ce149d..6018f5071d 100644
--- a/packages/query-core/src/query.ts
+++ b/packages/query-core/src/query.ts
@@ -250,7 +250,7 @@ export class Query<
   isStale(): boolean {
     return (
       this.state.isInvalidated ||
-      !this.state.dataUpdatedAt ||
+      this.state.data === undefined ||
       this.#observers.some((observer) => observer.getCurrentResult().isStale)
     )
   }
@@ -258,7 +258,7 @@ export class Query<
   isStaleByTime(staleTime = 0): boolean {
     return (
       this.state.isInvalidated ||
-      !this.state.dataUpdatedAt ||
+      this.state.data === undefined ||
       !timeUntilStale(this.state.dataUpdatedAt, staleTime)
     )
   }
@@ -329,7 +329,7 @@ export class Query<
     fetchOptions?: FetchOptions,
   ): Promise<TData> {
     if (this.state.fetchStatus !== 'idle') {
-      if (this.state.dataUpdatedAt && fetchOptions?.cancelRefetch) {
+      if (this.state.data !== undefined && fetchOptions?.cancelRefetch) {
         // Silently cancel current fetch if the user wants to cancel refetch
         this.cancel({ silent: true })
       } else if (this.#promise) {
@@ -546,7 +546,7 @@ export class Query<
             fetchStatus: canFetch(this.options.networkMode)
               ? 'fetching'
               : 'paused',
-            ...(!state.dataUpdatedAt && {
+            ...(state.data === undefined && {
               error: null,
               status: 'pending',
             }),
diff --git a/packages/query-core/src/queryObserver.ts b/packages/query-core/src/queryObserver.ts
index b972ab3fef..506a353dc8 100644
--- a/packages/query-core/src/queryObserver.ts
+++ b/packages/query-core/src/queryObserver.ts
@@ -444,7 +444,7 @@ export class QueryObserver<
         fetchStatus = canFetch(query.options.networkMode)
           ? 'fetching'
           : 'paused'
-        if (!state.dataUpdatedAt) {
+        if (state.data === undefined) {
           status = 'pending'
         }
       }
@@ -536,6 +536,7 @@ export class QueryObserver<
     const isError = status === 'error'
 
     const isLoading = isPending && isFetching
+    const hasData = state.data !== undefined
 
     const result: QueryObserverBaseResult<TData, TError> = {
       status,
@@ -558,10 +559,10 @@ export class QueryObserver<
         state.errorUpdateCount > queryInitialState.errorUpdateCount,
       isFetching,
       isRefetching: isFetching && !isPending,
-      isLoadingError: isError && state.dataUpdatedAt === 0,
+      isLoadingError: isError && !hasData,
       isPaused: fetchStatus === 'paused',
       isPlaceholderData,
-      isRefetchError: isError && state.dataUpdatedAt !== 0,
+      isRefetchError: isError && hasData,
       isStale: isStale(query, options),
       refetch: this.refetch,
     }
@@ -683,7 +684,7 @@ function shouldLoadOnMount(
 ): boolean {
   return (
     options.enabled !== false &&
-    !query.state.dataUpdatedAt &&
+    query.state.data === undefined &&
     !(query.state.status === 'error' && options.retryOnMount === false)
   )
 }
@@ -694,7 +695,7 @@ function shouldFetchOnMount(
 ): boolean {
   return (
     shouldLoadOnMount(query, options) ||
-    (query.state.dataUpdatedAt > 0 &&
+    (query.state.data !== undefined &&
       shouldFetchOn(query, options, options.refetchOnMount))
   )
 }
diff --git a/packages/query-core/src/tests/query.test.tsx b/packages/query-core/src/tests/query.test.tsx
index 632bc8636f..909cdbb6a0 100644
--- a/packages/query-core/src/tests/query.test.tsx
+++ b/packages/query-core/src/tests/query.test.tsx
@@ -841,6 +841,24 @@ describe('query', () => {
     expect(initialDataUpdatedAtSpy).toHaveBeenCalled()
   })
 
+  test('should work with initialDataUpdatedAt set to zero', async () => {
+    const key = queryKey()
+
+    await queryClient.prefetchQuery({
+      queryKey: key,
+      queryFn: () => 'data',
+      staleTime: Infinity,
+      initialData: 'initial',
+      initialDataUpdatedAt: 0,
+    })
+
+    expect(queryCache.find({ queryKey: key })?.state).toMatchObject({
+      data: 'initial',
+      status: 'success',
+      dataUpdatedAt: 0,
+    })
+  })
+
   test('queries should be garbage collected even if they never fetched', async () => {
     const key = queryKey()
 
diff --git a/packages/query-persist-client-core/src/__tests__/createPersister.test.ts b/packages/query-persist-client-core/src/__tests__/createPersister.test.ts
index e7ae8f3538..9aece2fcd2 100644
--- a/packages/query-persist-client-core/src/__tests__/createPersister.test.ts
+++ b/packages/query-persist-client-core/src/__tests__/createPersister.test.ts
@@ -207,7 +207,7 @@ describe('createPersister', () => {
     )
 
     await persisterFn(queryFn, context, query)
-    query.state.dataUpdatedAt = 0
+    query.state.data = 'data0'
     query.fetch = vi.fn()
     expect(query.state.dataUpdatedAt).toEqual(0)